ABSTRACT
Objective:To explore the effect of 14-3-3εprotein on the localization of Cdc25B protein during the meiotic resumption of mouse oocytes,and to pay foundation for the further study on the molecular mechanism of 14-3-3εprotein in regulating the development of mouse oocytes.Methods:The Kunming genealology female mice aged 3 weeks were used to obtain the germinal vesicle (GV)-stage oocytes after superovulation.The GV-stage oocytes were divided into non-injection group,control siRNA injection group and 14-3-3εsiRNA injection group. The pmax-FP-Red-HA-14-3-3εexpression vector was constructed.Indirect immunofluorescence was used to observe the colocalization of 14-3-3εprotein and Cdc25B protein in the mouse oocytes;direct immunofluorescence was used to observe the subcellular localization of 14-3-3εprotein and Cdc25B protein in the mouse oocytes;14-3-3εsiRNA was microinj ected into the GV-stage oocytes;the morphology was observed under phase-contrast microscope;the germinal vesicle breakdown (GVDB)rates of the mouse oocytes were calculated;the expression level of 14-3-3εprotein and the relative expression level of Cdc2-pTyr15 protein were observed by Western blotting method;the matuation-promoting factor (MPF)activity in the oocytes was measured by autoradiography.Results:The indirect immunofluorescence and direct immunofluorescence results showed that the 14-3-3εprotein and wild Cdc25B protein were co-localized in the cytoplasm;Cdc25B was translocated from the cytoplasm to the nucleus shortly before GVBD.When the Ser321 of Cdc25B protein turned into Ala,the expression level of 14-3-3εprotein was decreased. None of the oocytes in non-injection group and control siRNA injection group were able to undergo GVBD until at least 24 h after injection,there was no significant differences in the rate of GVBD between non-injection group and control siRNA injection group (P>0.05);the GVBD rates of oocytes in 14-3-3εsiRNA injection group at 22 and 24 h after injection were significantly higher than those in non-injection group and control siRNA injection group (P<0.01);the rate of oocytes progressed to metaphaseⅡ (MII)in 14-3-3εsiRNA injection group at 24 h after injection was significantly higher than those in non-injection group and control siRNA injection group (P<0.01). Conclusion:Ser321 might be involved in the process of regulating the subcellular localization of Cdc25B by 14-3-3εprotein in the meiotic resumption of mouse oocytes.
ABSTRACT
Objective:To study the role of 14-3-3εand Cdc25B in germinal vesicle (GV)-stage arrest of mouse oocytes,and to pay foundation for further study on the molecular mechanism of PKA/Cdc25B/14-3-3εpathway in GV-stage arrest of mouse oocytes.Methods:The eukaryotic expression vectors of pcDNA3.1-ZEO-HA-14-3-3ε, pcDNA3.1-MYC-Cdc25B-WT, pcDNA3.1-MYC-Cdc25B-S321A, and pcDNA3.1-MYC-Cdc25B-S321D were transcribed into mRNA invitro.The mouse GV-stage oocytes were collected after superovulation and divided into no injection group,TE buffer microinjection group,14-3-3εmRNA injection group,14-3-3εmRNAs + Cdc25B-WT mRNA injection group,and 14-3-3εmRNA + Cdc25B-S321A mRNA injection group,14-3-3εmRNA+Cdc25B-S321D mRNA injection group.The protein expression levels of HA-14-3-3εand MYC-Cdc25B and the phosphorylation status of Cdc2-pTyr15 were observed by Western blotting method.The morphological changes and germinal vesicle breakdown (GVDB)rates of mouse oocytes were observed under phase-contrast microscope. Results:None of the oocytes in no injection group, TE buffer microinjection group, 14-3-3εmRNA injection group,14-3-3εmRNA + Cdc25B-WT mRNAs injection group and 14-3-3εmRNA + Cdc25B-S321D mRNA were able to undergo GVBD until at least 20 h after injection (P>0.05 );the GVBD rates of oocytes in 14-3-3εmRNA+Cdc25B-S321A mRNA group at 1 h (5.00%±0.68%),2 h (62.00%±3.56%)and 3 h (100.00%± 0.00%)after injection were significantly higher than those in no injection group and TE buffer injection group (P<0.01);the oocytes in 14-3-3εmRNA+ Cdc25B-Ser321A mRNA group at 20 h (79.00%±2.80%)after injection progressed to MII (P<0.01).Conclusion:14-3-3εcan regulate the transition from GV to GVBD of mouse oocytes by means of phosphorylation and dephosphorylation of S321-Cdc25B.
ABSTRACT
Objective To investigate the expression of 14-3-3ε protein in the bladder urothelial carcinoma (BUC) and to explore its association with the clinicopathologic features.Methods The bladder urothelial carcinoma samples were divided into three groups:normal control group of 10 cases,low-grade malignant BUC group of 25cases (includes 5 cases of papilloma,10 cases of PUNLMP and 10 cases of low grade non-invasive papillary urothelial carcinoma),high-grade malignant BUC group of 21 cases (includes 11 cases of high-grade non invasive papillary urothelial carcinoma and 10cases of infiltrating carcinoma).The expression and location of 14-3-3ε in three groups were detected by immunohistochemical EnVision and the relationship with clinicopathologic parameters was analyzed.Results 14-3-3ε expression was observed in the cytoplasm of the cell.The expression of 14-3-3ε in normal control group was 90 ％ (9/10),low-grade malignant BUC group was 72.0 ％ (18/25),high grade malignant BUC group was 14.3 ％ (3/21).It correlated with histological grading but had not showed correlation with other clinicopathologic parameters.There was significant difference in 14-3-3ε expression between the high grade malignant BUC group and the low-grade malignant BUC group,the high grade malignant BUC group and norml control group (all P ＜ 0.05).Conclusions 14-3-3ε plays an important role in carcinogenesis of BUC.It may be a biomarker for early diagnosis and classification of BUC and shows promise for clinic application.